The fashion industry is beginning to understand the need to move strategically towards sustainability. Yet there appears at present little coordination between global fashion brands and their supply chains to pursue strategic sustainable development and ensure the long term resilience of their business. We asked: What does a fashion brand need to know about its first tier suppliers in China in order to form a strategy towards sustainability? We utilised a scientific, principle-based definition of sustainability and framework to identify the underlying challenges faced by two Chinese garment factories in moving strategically towards sustainability. The challenges enabled us to inform three strategic guidelines that a fashion brand should consider when working with its supply chain towards sustainability. Research draws on literature, interviews among industry experts, interviews with a major fashion brand, and on-site workshops with two of its first-tier garment factories in China. The results of our research indicate: 1) the specific challenges factories face are commonly associated with internal corporate culture, the fashion brand’s directives, and the regulatory environment in China; 2) the fashion brand should aim to broaden its purchasing priorities, generate increased collaboration with suppliers and build awareness towards empowerment and ownership of sustainability and associated strategies and actions.